I've played many many SP games since release and have never once been bothered by the lack of save game feature.
When I play, I *am* my Pretender. If I make a mistake, and I do often, I view that battle time and again, to understand what went bonkers - and improve, hopefully, the next time around. The lack of save game 'feature' adds a sense of permanence and, dare I type it, reality to the game. This isn't a game for little babies or people with an half an hour per week and expecting a quick fix. It was never meant to be, if I'm understanding its history correctly. It's immersive strategy writ large.
If programming time is going to be spent on implementing anything, save games ought to be waaaay down the list.
And hey, I like the 'sack up' jokeyness. So, you know.
Sack it up.